The phrase "alleged pattern" is correct and usable in written English.
It can be used when discussing a pattern that is claimed or reported but not yet proven or confirmed.
Example: "The investigation revealed an alleged pattern of misconduct within the organization."
Alternatives: "purported pattern" or "claimed pattern".
Green said, looking back on the comedian's alleged pattern, that Cosby selected his women carefully.
The Irving school district is also under investigation by the US Department of Justice over an alleged pattern of discrimination against minority students.
He urged those listening to check the history, to look at an alleged pattern of intent that led Greinke to hit him again.
On Wednesday the Guardian reported court records indicating the senior officer involved in Gray's arrest had engaged in an alleged "pattern of intimidation and violence", which led to a temporary restraining order being granted in 2013.
Bill Cosby's alleged pattern of drugging and raping women dates back to the 1960s, but he was not publicly held to account until 2014.
(That statistic includes workers who sign NDAs after finalizing a settlement; several women who knew about Harvey Weinstein's alleged pattern of sexual harassment, for example, signed such NDAs).
The suit, which alleged a "pattern or practice" of misconduct by the LAPD, was prompted by revelations of corruption in an anti-gang unit known as CRASH, Community Resources Against Street Hoodlums.
Trump's comments prompted much sharper criticism from Democrats, who alleged a pattern of coddling authoritarian leaders.
— The Illinois Senate removed Gov. Rod R. Blagojevich from office Thursday, convicting him on an article of impeachment that alleged a pattern of abuse of power.
Mr. Kranarong alleged a pattern of slippery business practices that included "sales" that involved no exchanges of money, unregistered gifts that evaded taxes and stock transfers to people who earned no dividends.
Asante, who has played for Arsenal and Chelsea and is now at FC Rosengard, has her own complaints about the way she has been treated in the England set-up and said she could understand why Aluko had alleged a pattern was developing.
