List Roles for User

Get-UserRoles.ps1

function Get-UserRoles{
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true, Position=0)]
        [string]$Identity
    )
  $user = Get-User $Identity
  return Get-Role -Filter * | Where-Object { $_.IsMember($user,$true,$true) } 
}

Write-Host "Roles for ServicesAPI" -ForegroundColor Green
Get-UserRoles "sitecore\ServicesAPI"

Write-Host "Roles for Admin" -ForegroundColor Green
Get-UserRoles "sitecore\admin"