Here's how the Ninth Circuit describes the petitioner in this case:
"Petitioner Daniel Flores is a native and citizen of Mexico.
He came to the United States as a lawful permanent resident
in 1962 . . . . Starting in the 1970s, Flores began serving as a
confidential informant for law enforcement, participating in
undercover controlled drug buys and testifying against members of various gangs. Also around that time, Flores
began to amass a lengthy criminal record that culminated in
his pleading guilty in 1990 to two felony counts of
committing lewd and lascivious acts on a child under the age
of 14 in violation of California Penal Code § 288(a). Flores’s
conviction carried with it a six-year prison sentence, of which
he served three. He was released from prison on parole in
1994, discharged from parole in 1997, and has no further
criminal record.
After his release from prison, Flores worked in the
corporate security industry until 2002, when he stopped
working for health reasons. He resumed his role as a
confidential informant for law enforcement in 2008 but was
forced to discontinue his assistance in 2011 following foot
surgery. Today, Flores spends his time taking care of his
mother, who suffers from several serious medical conditions,
including epilepsy, Parkinson’s disease, and dementia."
That's a fairly positive description of the fellow. You could definitely write those same facts a different way to make him look far worse.