A Yukon teenager who helped chop off a drug dealer's finger will have to serve out his sentence in federal prison.

Judges of the Yukon court of Appeal have rejected the aboriginal man's pleas for a lesser term.

The judges agreed Michael Nehass needs help, but they say for the safety of others, he'll have to find that help in jail.

By the summer of 2003, Nehass was a seriously disturbed youth, addicted to booze and drugs, living on the streets of Whitehorse.

Despite being only 19, Nehass had a lengthy criminal record, and had just inherited $47,000 from his mother's estate.

On June 12, Nehass was among a gang of enforcers who invaded a downtown home to rough up a cocaine dealer known as "Mad Dog" Marten.

They beat him with clubs, then chopped off his little finger.

On the way out, Nehass butted a cigarette on the victim's back.

Sentenced to three years in prison, Nehass lawyer has appealed, citing his client's age and aboriginal background.

Judges are required to pay extra attention to circumstances of aboriginal offenders.

The Appeals court judges acknowledge Nehass' difficult and unfortunate background.

But they say his three-year prison sentence was fully justified.

One judge even suggested Nehass may have gotten off lightly for such a horrible crime.

The appeal was dismissed.