The Role of Jailhouse Informants in Long Island Criminal Trials

The Troubling Role of Jailhouse Informants in Long Island Criminal Trials

Jailhouse informants—inmates who testify against other defendants in exchange for leniency—have become nearly ubiquitous in criminal trials across the country. While prosecutors maintain these witnesses provide critical testimony to secure convictions against dangerous criminals, critics argue they incentivize perjury and have contributed to numerous wrongful convictions.

As a criminal defense lawyer practicing on Long Island for over 15 years, I’ve seen my fair share of jailhouse informants testifying in local cases. And I have serious concerns about reliance on their statements. There are few regulations around use of inmate testimony, which opens the door to major problems down the line—not the least of which is convicting innocent people.

In this article, I’ll break down the issues around jailhouse informants in Long Island courts, highlight some recent local cases involving problematic use of inmate witnesses, and discuss potential policy solutions to address this critical gap in our criminal justice system.

The Troubling Incentive Structure for Jailhouse Informants

Offering significant incentives for testimony—while failing to corroborate the substance—encourages lying on the stand. And the potential benefits for informants are substantial. Prosecutors routinely offer reduced charges or sentences, improved jail conditions, cash payouts, and other enticements in exchange for cooperation.

For inmates already serving time, there is little to lose and much to gain by making up statements and attributing them to a high-profile defendant. Even if the statements are fabricated, they still reap the rewards.

This troubling incentive structure leads directly to false testimony. And once an informant lies on the stand, it is incredibly difficult to undo the damage. Appellate courts grant substantial deference to jury verdicts, meaning convictions are rarely overturned due to issues around witness credibility.

High Profile Long Island Cases Involving Jailhouse Informants

There is perhaps no more emblematic case on Long Island involving problematic use of a jailhouse informant than the trial of Martin Tankleff in 1988. Tankleff was convicted of murdering his parents based predominantly on the testimony of career criminal Glenn Harris.

Harris, who was housed in the same jail awaiting trial for an unrelated burglary, testified Tankleff confessed the murders to him. In exchange, Harris received a reduced 5-year sentence for his own crimes.

Yet Harris’s account was contradicted by forensic evidence. And he failed to provide a single verifiable detail from his supposed conversation with Tankleff. After serving 17 years in prison for the murders, Tankleff’s conviction was vacated in 2007. Prosecutors ultimately dropped all charges, although they maintained his guilt.

The Tankleff case is far from the only high-profile Long Island matter involving jailhouse informants. In 2010, defendant Wayne Gulick had his conviction for a 2004 murder overturned after the credibility of prosecution witness Michael Lloyd crumbled under scrutiny.

Lloyd claimed Gulick confessed to the crime during a brief jailhouse conversation. But Lloyd’s extensive history of dishonesty—including four prior instances of testifying against other inmates—gave credence to accusations that Lloyd fabricated the confession.

Just this year, witness credibility issues around career jailhouse informant James Bannister led a judge to overturn Jermaine Dunbar’s murder conviction. Bannister alleged Dunbar admitted to a 2008 killing during a chance encounter in a jail visiting area.

But the court found serious inconsistencies in Bannister’s statements about the purported confession. Dunbar maintained his innocence and argued Bannister lied about the confession to gain sentencing leniency. Prosecutors ultimately chose not to retry the case given the doubts around their key witness.

Policy Solutions for More Reliable Testimony

So what can courts do to address credibility issues around jailhouse informants? Most importantly, we need clear procedures ensuring this testimony is corroborated before it gets to a jury.

States like Illinois and Texas have instituted important reforms requiring informants provide verified evidence backing up their statements—not just their word. Some jurisdictions also mandate full disclosure of an informant’s history of cooperation and benefits received.

Prosecutors are also barred from making promises of leniency until after an informant testifies truthfully. This prevents scenarios where witnesses fabricate testimony to gain promised rewards, only to have their lies exposed at trial.

While national innocence organizations advocate banning informant testimony altogether, that seems unlikely given courts’ general acceptance of these witnesses. But at a minimum, Long Island courts should adopt rigorous corroboration and disclosure rules before allowing inmates to take the stand.

The Role of Defense Lawyers in Contesting Jailhouse Informants

Beyond policy reforms, there is also an essential role for defense lawyers in contesting problematic jailhouse informant testimony. Establishing a witness’s history of dishonesty and thorough cross examination into the substance of their statements are critical.

But that is only half the battle. Equally important is explaining to juries how the incentives offered informants encourage false testimony. Research shows people generally struggle to discount information they are told is unreliable or inaccurate. So directly confronting credibility concerns is key.

Highlighting inconsistencies between forensic evidence and informant statements also helps undermine their accounts. Of course, part of the problem is many cases hinge almost entirely on informant testimony, with no scientific evidence to contradict them. But where possible, comparing the two can be highly effective.

Broader Implications of Unreliable Jailhouse Informant Testimony

The problems with jailhouse informants have implications far beyond individual cases. Reliance on potentially fabricated testimony to secure convictions strikes at the heart of due process and the presumption of innocence. It shakes public faith in the courts and compounds errors that ruin lives.

And while DNA testing has exposed many wrongful convictions stemming from lying informants, the vast majority of cases lack biological evidence to prove innocence post-conviction. Meaning for every exoneration, far more tainted verdicts likely stand uncorrected.

Allowing incentivized witnesses free rein to provide unverified—and often completely fabricated—statements against defendants facing decades behind bars cannot stand. Just as defendants have rights, so too do informants have responsibilities. And Long Island courts must enact rigorous safeguards to ensure testimony is honest before allowing it near a courtroom.

The well-documented injustices wrought by unchecked jailhouse informants demand nothing less. The next innocent defendant sent to prison based on a made up confession is one too many. It is past time for reform